Rotary piston expansible chamber machine



March 7, 1967 J. B. M CLURE 3,307,525

' ROTARY PISTON EXPANSIBLE CHAMBER MACHINE Filed May s, 1964. sSheets-Sheet 1 James 5. Ma C/ure INVENTOR.

M a Anarne s March 7, 1967 J. B. MCQ URE 3,307,525

ROTARY PISTON EXPANSIBLE CHAMBER MACHINE Filed May 5, 1964 6Sheets-Sheet 2 James B. McClure INVENTOR.

a 11-: r Attorney:

March 7, 1967 J. B. M CLURE 3,307,525

ROTARY PISTON EXPANSIBLE CHAMBER MACHINE I Filed May 5, 1964 6Sheets-Sheet 3 Fig. 6

James B. McClure INVENTOR;

March 7, 1967 J B. M CLURE ROTARY PISTON EXPANSIBLE CHAMBER MACHINE 6Sheets-Sheet 4 Filed May 5, 1964 INVENTOR.

1 James 8. Ma C/ure March 7, 1967 J. B. M CLURE ROTARY PISTON EXPANSIBLECHAMBER MACHINE 6 Sheets-Sheet 5 Filed May 5, 1964 M a w m m E V m Mam}!1967 J. B. M CLURE 3,307,525

ROTARY PISTON EXPANSIBLE CHAMBER MACHINE Filed May 5, 1964 sSheets-Sheet e flames B. McClure INVENTOR.

United States Patent Ofiice 3,307,525 Patented Mar. 7, 1967 3,307,525ROTARY PISTON EXPANSIBLE CHAMBER MACHINE James B. McClure, Mercury,Nev., assignor to McClure Corporation of America, a corporation ofNevada Filed May 5, 1964, Ser. No. 365,042 9 Claims. (Cl. 123-8) Thisinvention comprises a novel and useful rotary piston expansible chambermachinc.

This invention comprises a novel and useful rotary piston expansiblechamber machine and while pertaining generally to expansible chamberdevices of the rotary piston positive displacement type, it isparticularly concerned with an internal combustion engine of thatgeneral type.

The primary object of this invention is to provide a positivedisplacement expansible chamber device which, although not limitedthereto, is especially adapted to function as an internal combustionengine and wherein a plurality of expansible chambers are providedwithin a stator in which a single rotor providing a plurality of pistonsmoves progressively about the series of chambers in the stator thusproviding a plurality of complete cycles of operation for a singlerotation of the drive shaft and rotor.

A further object of the invention is to provide a device in which aunidirectional rotation of the piston is substituted for theconventional reciprocating piston usually employed in internalcombustion engines.

A further object of the invention is to provide a device in accordancewith the foregoing objects in which the pistons have a relative slidingand sealed engagement with the Walls of the chambers and moveprogressively into and out of a series of chambers during a singlerevolution of the drive shaft.

A still further object of the invention is to provide a device having animproved fluid inlet and exhaust system controlled by a very simplerotary valve element.

Yet another purpose of the invention is to provide a device incompliance with the preceding objects which shall utilize a two-piececrankshaft thus enabling easy assembly and disassembly of the enginewith the ends of the cranksha-ft being in juxtaposition and in alignmentwith each other and journaled in the hub of the rotor.

Still another purpose of the invention is to provide a device as setforth in the foregoing objects which shall have an improved sealingmeans on the piston element of the rotor and one which will yieldinglyelongate itself axially of the device for taking up wear and clearancein the Working chamber of the device.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a top plan view of a preferred embodiment of the inventionwhich as illustrated in the accompanying drawings and described in theaccompanying specification is an internal combustion engine;

FIGURE 2 is a side elevational view of the arrangement of FIGURE 1;

FIGURE 3 is an end elevational view from the left end of FIGURES 1 and2, parts being broken away and other parts being shown in dotted lines;

FIGURE 4 is an end elevational view from the right end of FIGURES 1 and2, certain concealed parts being shown in dotted lines;

FIGURE 5 is a central horizontal sectional View taken upon an enlargedscale substantially upon the plane indicated by the section line 55 ofFIGURE 2 and showing the fluid passage system and one of the sealingmeans of the invention;

FIGURE 6 is a further view in central vertical section taken upon anenlarged scale substantially upon the plane indicated by the sectionline 6--6 of FIGURE 1 and showing more clearly the rotor of the engine;

FIGURE 7 is a view in vertical transverse section taken substantiallyupon the plane indicated by the section line 77 of FIGURE 5 with partsbroken away and shown in section and showing more clearly the locationand disposition of the working chambers of the device;

FIGURE 8 is a view in vertical transverse section taken substantiallyupon the plane indicated by the section line 8-8 of FIGURE 5 and showingin particular the intake and exhaust port arrangement of the inventionand the rotary valve element thereof;

FIGURE 9 is a fragmentary view in vertical transverse section takensubstantially upon the plane indicated by the section line 99 of FIGURE6 and showing certain details of the sealing means of the rotor unit ofthe engine;

FIGURE 10 is a view in vertical longitudinal section, parts being brokenaway and omitted, taken substantially upon the plane indicated by thesection line 1010 of FIGURE 9 and showing further details of the sealingmeans for the piston blades;

FIGURE 11 is an exposed perspective view of one of the rotor pistonblade sealing assemblies;

FIGURE 12 is a perspective view of the rotary valve disk which controlsthe intake and exhaust of the engine;

FIGURE 13 is an exploded perspective view of the rotor and a portion ofthe two-piece engine crankshaft associated therewith; and

FIGURE 14 is a composite view showing diagrammatically the sequence ofmovements of the rotor pistons in the working chambers at successivepositions during a complete cycle of the operation of the engine.

Although the principles of the invention are applicable to fluid motors,external combustion engines and pumps and compressors, there isdisclosed specifically herein as a manner of applying the principles ofthe invention an internal combustion engine construction.

Stator The internal combustion engine illustrated in the drawings isindicated generally by the numeral 10 and may be of any suitable shapeand size being illustrated as of square cross-section. The engineincludes a stator together with a rotor movably mounted therein.

The stator as may be best seen from FIGURES 1, 2, 5 and 6, consists of acentral casing section 12 having open ends to which are secured a pairof axially aligned manifold sections 14 and 16. The section 16 in turnis provided with an end plate 18 while the section 14 has a valve casing20 together with an end plate 22. These sections are axially alignedwith each other and are of the same external cross-sectional shape andare detachably secured together as by through bolts 24, suitable sealingrings such as those shown at 26 in FIGURE 5 being posi tioned betweenthe mating surfaces of the various sections.

It will be observed that the manifold sections 14 and 16 are hollow orprovided with passages therein and these sections provide side walls 28for the section 16 and 30 for the section 14, see FIGURE 6- inparticular, while the section 12 has an inner peripheral wall 32 of anundulating configuration with successive portions being at varyingdistances from the center of the stator. The peripheral and side wallsdefine therebetween a generally polygonal-shaped compartment within thestator which as shown best in FIGURE 7 is bounded by four convex wallswith radially outwardly projecting recesses being provided betweenadjacent convex wall portions. Each of the convex wall portions isindicated by the numeral 34 while the interposed radially projectingrecesses are indicated at 36 and as will be apparent comprise pockets.

Ignition means of any suitable type such as the spark plugs 38 areprovided upon opposite sides of the stator central section andcommunicate as by ignition passages 40 extending through the convexwalls 34 into opposite sides of the central compartment and adjacentopposite pockets or recesses 36. Any suitable ignition system isconnected to these spark plugs, but inasmuch as the details of theignition system are well understood by those skilled in the art and formno part of the invention set forth in the claims hereinafter a furtherdescription thereof is deemed to be unnecessary. It will of course beappreciated that when the device is to function as a fluid motor, acompressor or the like, that the spark plugs and their ignition systemand ignition passages may be omitted.

As will be further observed from FIGURE 3, suitable supporting bracketsas at 42 may be provided upon any desired portion of the stator and itssection to constitute a means for mounting the device upon any suitablefoundation or support structure.

As will be best observed from FIGURE 5, the end plate 22 which isengaged upon and forms a closure for the valve casting 20 is providedwith an annular exhaust collection chamber 44 therein which discharges,as for example by the exhaust conduit 46, see FIGURE 2, to theatmosphere or any other suitable place of discharge. A combustiblemixture from any suitable source, not shown, is supplied to the valvecasing 22 as by means of the conduit 48 and thus discharging to theannular internal chamber of the valve casing.

Referring now to FIGURE 12 in conjunction with FIG- URES 5, 6 and 8, itwill be observed that there is provided a disk valve 50 having a centralopening 52 by which it is secured upon the drive shaft of the rotor in amanner to be subsequently set forth. This valve is in the form of a diskor plate having an arcuately extending slot 54- therethroughconstituting the exhaust port of the valve together with an arcuatelyextending recess 56 in its periphery opposite the slot 54 whichconstitutes the combustible mixture inlet port of the valve. It will beobserved that the manifold section 14 has appropriately disposed axiallyextending exhaust and intake ports 58 and 60, respectively, whoseopposite ends communicate with the compartment within the stator and inproper sequence with the exhaust and intake ports 54 and 56 in the valvedisk. Similarly, the intake 22 includes exhaust ports 62 which arepositioned to likewise register with the manifold collection chamber 44and the exhaust port 54 of the valve disk member.

A water jacketing cooling system may be conveniently employed with thisinvention. A portion of this water jacket is shown in FIGURES 5, 6, 9and at 64, including chambers formed in the manifold sections M- and 16and connected by passages through the central casing section 12. Sincethe cooling system forms no part of the invention claimed herein, afurther description is deemed to be unnecessary.

Rotor assembly Cooperating with the stator is a rotor assembly. Thisincludes a rotor in the form of a central portion or hub 70 having aplurality of radially outwardly extending blades or vanes each indicatedby the numeral 72 which comprise the pistons of the apparatus. As shown,the rotor for the four-sided compartment is of triangular configurationhaving three blades 72. A bearing bushing or sleeve 74, see FIGURE 10,is disposed in an axial bore through the rotor and serves to journal thelatter upon a drive shaft indicated generally by the numeral '76.

The rotor which is designated in its entirety by the numeral isrotatably mounted upon the drive shaft but eccentrically of the driveshaft axis. It will be observed that the drive shaft 76 is disposedaxially or centrally of the compartment within the stator while therotor 80 is positioned eccentrically of or to one side of thecompartment as the rotor moves progressively about the compartment.

The drive shaft 76 is preferably composed of two sections eachcomprising a crankshaft consisting of the main crankshaft portion 82,see FIGURE 13, carrying a crank throw in the form of a disk 84 uponwhich is carried an eccentrically disposed cylindrical crank pin 86. Thetwo crankshaft sections extend in axial alignment with each otherthrough suitable bearing bushings 87 and 89 which are engaged in the endwall 18 and in an axially extending internally threaded projection 88 ofthe manifold section 16 and in the inner wall of the valve casing 20 andthe other manifold section 14.

If desired one of the crankshaft sections may terminate in its bearingassembly but at least one of the sections projects axially through theend wall of the device to receive thereon a flywheel 89. Power may betaken off from either of the crankshaft portions when the devicefunctions as an internal combustion engine or the fluid motor, or bywhich power may be supplied to the rotor when the device functions as apump or compressor.

Observing now FIGURE 10 in particular, it will be seen that the twocrankpins 86 are in axial alignment with each other and are receivedwithin the bushing 74 within the rotor hub 70. In this manner, thetriangularshaped rotor is eccentrically mounted with and rotatablysupported upon the'drive shaft 7 6 by the two sections 82 thereof. Theproportions of the parts are such that as the drive shaft rotates, theouter radial edges of the blades 72 will be caused to maintain a slidingcontact with the convex walls 34 of the compartment except as they moveinto the recesses or pockets 36. Suitable sealing means are provided forinsuring a fluid-tight engagement of the blades with the peripheral andside walls of the compartment in order that working chambers may bedefined between the blades, the side walls and the peripheral wall in amanner to be subsequently set forth. For this purpose, the throw 84 ofthe crankshaft is such that as the crankshaft rotates and the rotor hubmoves in an orbital path about the axis of the crankshaft, theeccentrically positioned blades will have an epicyclic motion wherebythey move while continuously in contact with the convex walls 34 andprogressively travel about the inner peripheral Wall while rotating in areverse direction upon rotation of the crankshaft.

Consequently, as will be noted from FIGURE 2 in conjunction with thediagrammatic views of FIGURE 14, each adjacent pair of blades definestherebetween and with the peripheral wall portions 34 of the compartmenta working chamber in which the volume is progressively expanded and thencontracted to thus perform the cyclic working strokes of the device.

For this purpose it is desirable that the rotor shall have a differentnumber of blades than the number of the recesses and compartments, therebeing shown three blades cooperating with the four recesses.

Blade sealing means As previously mentioned, a sealing means is providedfor each of the blades to establish and maintaina fluidtight seal of thelatter with the peripheral and side walls of the compartment during theorbital travel of the blades therein and a rotation of the blades duringsuch travel.

Referring first to FIGURE 9 it will be noted that the radial outer endsof each of the blades 72 has a semicylindrical recess 90 therein and acylindrical sealing element designated generally by the numeral 92 isreceived in this recess which constitutes a seat therefor. Moreover, aswill be best apparent from FIGURE 10, in corn junction with FIGURE 13,the end walls of the rotor are provided with radial grooves or recesses94 for the reception of sealing strips 95, see FIGURES and 11 inparticular, whereby the piston blades are sealed to the peripheral walland to the two side walls of the compartment in which they move.

Referring now especially to FIGURES 10 and 11 it will be observed thatthe cylindrical sealing element 92 consists of a pair of axially alignedcylindrical sections 96 and 98, having upon their adjacent ends axiallyextending fingers 100. As best seen in FIGURES 5 and 13, the fingers 100of the sections 96 and 98 are interengaged or digitated with respect toeach other while being capable of a limited axial relative movementtherebetween. Avguide member in the form of a bushing or sleeve 102 isslidably received within the interior of the sections 96 and 98 andunderlies the interengaged fingers 100 as best shown in FIGURE 10. Thissleeve is primarily a sealing means preventing the leakage of fluidpressure from the working chambers of the apparatus through the openingsbetween the interdigitated fingers 100 of the movable sections 96 and98. It also serves the dual functions of stiffening and reinforcing theinterdigitated connection of the cylindrical sections 96 and 98 as wellas constituting an inner abutment for a pair of springs 106, each ofwhich abuts against the guide member 102 and projects outwardlytherefrom and through the open ends at the outer sides of the sections96 and 98.

The sealing strips 95 previously mentioned include cylindrical caps 108upon their extremities which embrace diametrically reduced cylindricalend portions 110 of the two sections 96 and 98. The springs thus abutagainst the caps and urge them axially outwardly thereby pressing thestrips against the side walls 28 and 30. If desired, the caps may befixedly secured to the portions 110 of the sections and the springs alsoserve to resiliently urge the sections apart andthus tend to axiallyelongate or extend the cylindrical sealing elements 92.

Referring now particularly to FIGURES 7, 9 11, 13, it will beappreciated that the opposite ends of the rotor hub are provided withannular sealing ring grooves or channels 112 concentric with the bushing74 and which intersect the radial slots 94 of the sealing strips 95.Seated in each channel 112 is an annular sealing ring 114 urged by aspring 116 into resilient sealing engagement with the end walls 28 and30. The crossing portions of the strips 95 and rings 112 are notched orgained as at 119 and 121 so that their outer surfaces are flush whilethey establish a fluid-tight seal with each other.

Each of the rotor vanes or blades 72 has a radially extending andtransversely disposed pocket or clearance 118 which is rectangular incross-section and opens into the bottom of the recess 90 and receives asealing blade 120 therein. The ends of this blade are slidably andguidingly retained in the notches of the strips 95. The

adjacent edge of the blade 122 is concaved for sealing engagement withthe sealing element 92. A spring 124 in the pocket 118 urges the blade122 radially outwardly against the sealing element 92 and the latteragainst the peripheral wall 34 of the working chamber.

Operation The operation of the internal combustion engine illustratedherein is as follows. A combustible mixture of any suitable source isdelivered by the intake conduits 48 into the radially outer portion ofthe valve casing 22. From thence it is distributed by the inlet arcuaterecess 56 of the valve member 50 through registering ports in the valvecasing and the inlet passage of the manifold section 14 and into thecompartment of the device. The valve is so timed that as the associatedworking chamber of the compartment is expanding from its minimum volumetoward its maximum volume, the combustion mixture is supplied thereto.When the chamber reaches its maximum volume, and begins to contract, thevalve disk 50 closes the inlet port and the mixture is then compressedto its maximum as the working chamber decreases toward its minimumvolume. After sufficient compression has occurred, the igniting means 38ignites the charge and the working stroke of the engine begins, at whichtime the igniting combustible mixture Within the expanding workingchamber imparts rotation to the rotor and the drive shaft connectedthereto. As the working chamber approaches its maximum volume the valvedisk opens the exhaust port 58 of the working chamber to the exhaustcollection chamber 44 through the port 62 and the exhaust port whiledischarging therefrom. During this period the working chamber isdecreasing in volume thereby expellingfthe exhaust products, after whichthe cycle repeats itsel The sequence of operations will be more readilyapparent from a consideration of the diagrammatic views of FIGURE 14.Shown in that figure are 12 successive positions of the rotor in thecompartment during one complete revolution of the drive shaft. It willbe noted that certain intermediate positions have been omitted tosimplify the drawings in which each figure represents one of the 24circumferentially spaced positions of the rotor during its travel.Considering a single blade A comprising one of the pistons of the rotor,it will be noted that this blade in the 23 different positions has movedthrough one complete revolution within the compartment. It will be seenthat simultaneously the same movement is occurring for the other twoblades or pistons B and C. Each of the four recesses or pockets isdesignated by the letters D, E, F and G, while the successive convexportions of the combustion chamber periphery inner wall are indicated atH, I, J and K, respectively. The section of the rotor surface lyingbetween the blades A and B is identified as L, While that lying betweenB and C is indicated at M and that between C and A is identified at N.

In the position indicated by 1 in FIGURE 14, it will be noted that thechamber bounded by the walls N and K is at its minimum. Consequently,this chamber has just completed its exhaust stroke. In the positionshown at 2 this chamber lying between A and C is increasing its volumeand is thus on its intake or suction stroke, drawing in a combustiblecharge. This action continues through position 3, until it reaches itsmaximum volume in position 4. Thereafter, this chamber begins tocompress through the position of FIGURES 5 and 6 until it reachesmaximum compression in 7 at which time ignition occurs. Moving to theposition of FIGURE 7, this chamber increases in volume and is movingupon its expansion or working stroke as shown in 8. When it reaches theposition 11, the working stroke is completed, the exhaust port opens andthe exhaust is now beginning. This continues until the exhaust iscompleted, a new charge is taken in and in the position 19 the secondcharge is compressed and fired. The chamber then moves upon its workingstroke and then upon its exhaust stroke until as shown in 23 itapproaches its initial position. Thus, each chamber underlies twocomplete explositions during I one revolution. This action is occurringwhile the other three chambers simultaneously but at spaced intervals aswill be apparent from the diagrammatic views.

When the device is employed as a fluid motor or external combustionengine, the ignition system is unnecessary and pressure is supplied tothe inlet port and exhausted through the discharge ports upon the samecycle of operation. When the device is employed as a compressor, thesame cycle of operation is also effected.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. An expansible chamber device of the positive displacement rotarypiston type comprising a stator and rotor, said stator having therein agenerally polygonal-shaped compartment bounded by a pair of side wallsand an undulating peripheral wall, a drive shaft journaled in saidstator and disposed centrally of said compartment, said rotor beingdisposed in said compartment and mounted eccentrically and rotatablyupon said drive shaft, said rotor having a central hub with a pluralityof radially extending blades comprising pistons, sealing means carriedby said blades and having a sliding and sealing engage ment with saidperipheral and side walls, said blades, side walls and peripheral walldefining successive working chambers which expand and contractsuccessively upon movement of said pistons about said compartment, andfluid inlet and outlet means communicating with said chamber, saidsealing means comprising, a cylindrical sealing element in asemi-cylindrical, axially extending channel at the outer ends of eachblade, each sealing element comprising sealing strips on opposite ends,a pair of aligned, spaced cylindrical sections having interdigitated,axially extending fingers on adjacent ends, a cylindrical guide memberdisposed within said cylindrical sections overlapping the interdigitatedfingers, a pair of springs disposed on opposite sides of and abuttingthe guide member to yieldingly urge the sections apart for axially andresiliently extending the sealing strips into sealing engagement withsaid side walls, each of said strips having a cap portion embracing theouter end of a cylindrical section and engaging one of said springs.

2. The combination of claim 1 including resilient means in said rotorbut engaging said strips and yieldingly biasing them against said sidewalls.

3. An expansible chamber device of the positive displacement rotarypiston type comprising a stator and a rotor, said stator having thereina generally polygonalshaped compartment bounded by a pair of side wallsand an undulating peripheral wall, a drive shaft journaled in saidstator and disposed centrally of said compartment, said rotor beingdisposed in said compartment and mounted eccentrically and rotatablyupon said drive shaft, said rotor having a central hub with a pluralityof radially extending blades comprising pistons, sealing means carriedby said blades, and having a sliding and sealing engagement with saidperipheral and side walls, said blades, side walls and peripheral walldefining successive working chambers which expand and contractsuccessively upon movement of said pistons about said compartment, fluidinlet and outlet means communicating with said working chamber, saidstator comprising a central section having said compartment therein, apair of hollow manifold sec.- tions axially aligned with and engagingopposite open ends of said central section to form said side walls, avalve casing section axially aligned with and secured to one of saidmanifold sections, a pair of end plates secured respectively to andclosing the ends of said valve casing section and a disk valve in saidvalve casing independently driven by said drive shaft and control-lingflow through said ports.

4. The combination of claim 3 wherein said disk valve has an arcuateslot and an arcuate peripheral recess respectively registrable with saidoutlet and inlet ports.

5. The combination of claim 4 including an exhaust gas collector chamberin said end plate secured to said valve casing section and combustiblemixture inlet ports in said valve casing.

6. An expansible fluid chamber device comprising, a stator having sidewalls and a peripheral wall enclosing a fluid compartment, a rotoreccentrically mounted for rotation within said compartment and aplurality of blades slidingly mounted by said rotor, each of said bladesincluding sealing means having a pair of elements slidably mounted bythe rotor in sliding contact with said side walls, axially extensiblemeans supported by said pair of elements in sliding contact with theperipheral wall, and spring means mounted within the axially extensiblemeans. biasing said pair of elements into sealing engagement with theside walls.

'7. An expansible fluid chamber device comprising, a stator having ahousing section peripherally enclosing a fluid compartment and manifoldsections forming axially spaced side walls closing said fluidcompartment, a power shaft rotatably mounted by the stator and extendingthrough the fluid compartment, a rotor eccentrically mounted by theshaft within the fluid compartment, a plurality of blades mounted by therotor dividing the fluid compartment into expansible working chambers,valve means independently driven by said power shaft for conductingfluid to and from said Working chambers through one of the manifoldsections of the stator, and axially biased sealing means supported byeach of the blades in sealing engagement with both the side walls of themanifold sections and the housing section of the stator.

8. The combination of claim 7 wherein said valve means includes a discmember having an arcuate exhaust port extending therethrough for axialdischarge of fluid from said working chambers, and an arcuate recessestablishing fluid communication between a radial inlet port in thestator and the working chambers.

9. The combination of claim 8 wherein said sealing means includes a pairelements slidably mounted by the rotor in sliding contact with said sidewalls, axially extensible means supported by said pair of elements insliding contact with the housing section, and spring means mountedwithin the axially extensible means biasing said pair of elements intosealing engagement with the side walls.

References Cited by the Examiner UNITED STATES PATENTS 2,162,771 6/1939Wimans. 2,866,417 12/1958 Nubling. 2,958,312 11/1960 Shimomura 123-132,994,277 8/ 1961 Merritt. 3,056,391 10/1962 Hoadley. 3,082,747 3/1963Luck. 3,199,496 8/1965 Kell 1238 3,224,421 12/ 1965 Peras 1238 FOREIGNPATENTS 853,807 12/1939 France.

1,328,929 4/1963 France.

24,559 1908 Great Britain.

61,871 8/1923 Sweden.

MARK NEWMAN, Primary Examiner. F. T. SADLER, Assistant Examiner.

1. AN EXPANSIBLE CHAMBER DEVICE OF THE POSITIVE DISPLACEMENT ROTARYPISTON TYPE COMPRISING A STATOR AND ROTOR, SAID STATOR HAVING THEREIN AGENERALLY POLYGONAL-SHAPED COMPARTMENT BOUNDED BY A PAIR OF SAIDE WALLSAND AN UNDULATING PERIPHERAL WALL, A DRIVE SHAFT JOURNALED IN SAIDSTATOR AND DISPOSED CENTRALLY OF SAID COMPARTMENT, SAID ROTOR BEINGDISPOSED IN SAID COMPARTMENT AND MOUNTED ECCENTRICALLY AND ROTATABLYUPON SAID DRIVE SHAFT, SAID ROTOR HAVING A CENTRAL HUB WITH A PLURALITYOF RADIALLY EXTENDING BLADES COMPRISING PISTONS, SEALING MEANS CARRIEDBY SAID BLADES AND HAVING A SLIDING AND SEALING ENGAGEMENT WITH SAIDPERIPHERAL AND SIDE WALLS, SAID BLADES, SIDE WALLS AND PERIPHERAL WALLDEFINING SUCCESSIVE WORKING CHAMBERS WHICH EXPAND AND CONTRACTSUCCESSIVELY UPON MOVEMENT OF SAID PISTONS ABOUT SAID COMPARTMENT, ANDFLUID INLET AND OUTLET MEANS COMMUNICATING WITH SAID CHAMBER, SAIDSEALING MEANS COMPRISING, A CYLINDRICAL SEALING ELEMENT IN ASEMI-CYLINDRICAL, AXIALLY EXTENDING CHANNEL AT THE OUTER ENDS OF EACHBLADE, EACH SEALING ELEMENT COMPRISING SEALING STRIPS ON OPPOSITE ENDS,A PAIR OF ALIGNED, SPACED CYLINDRICAL SECTIONS HAVING INTERDIGITATED,AXIALLY EXTENDING FINGERS ON ADJACENT ENDS, A CYLINDRICAL GUIDE MEMBERDISPOSED WITHIN SAID CYLINDRICAL SECTIONS OVERLAPPING THE INTERDIGITATEDFINGERS, A PAIR OF SPRINGS DISPOSED ON OPPOSITE SIDES OF AND ABUTTINGTHE GUIDE MEMBER TO YIELDINGLY URGE THE SECTIONS APART FOR AXIALLY ANDRESILIENTLY EXTENDING THE SEALING STRIPS INTO SEALING ENGAGEMENT WITHSAID SIDE WALLS, EACH OF SAID STRIPS HAVING A CAP PORTION EMBRACING THEOUTER END OF A CYLINDRICAL SECTION AND ENGAGING ONE OF SAID SPRINGS.